Re: [PATCH v3 0/2] nfsd: sanely handle inabilty to fetch pre/post attributes

[Chuck Lever]

On Fri, Jul 21, 2023 at 10:29:09AM -0400, Jeff Layton wrote:
> Boyang reported tripping the BUG_ON in set_change_info. While we
> couldn't confirm it, one way this could happen would be for nfsd_lookup
> to succeed and then for fh_fill_both_attrs to fail.
> 
> This patchset attempts to (sanely) fix this, usually by aborting the
> operation if fetching the pre attributes fails. Post-op attribute fetch
> handling is more difficult to deal with however since we've already done
> the operation, so this has it just fudge the change_info4 if that
> occurs.
> 
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>

Applied v3 to nfsd-next. Thanks!


> ---
> Changes in v2:
> - rework the error paths to consistently use gotos
> - add __must_check to fh_fill_pre_attrs and fh_fill_both_attrs
> - fix bad error handling in setxattr codepath
> 
> ---
> Jeff Layton (2):
>       nfsd: handle failure to collect pre/post-op attrs more sanely
>       nfsd: remove unsafe BUG_ON from set_change_info
> 
>  fs/nfsd/nfs3proc.c |  4 +++-
>  fs/nfsd/nfs4proc.c | 46 ++++++++++++++++++++++++++++++++++++++++------
>  fs/nfsd/nfsfh.c    | 26 ++++++++++++++++----------
>  fs/nfsd/nfsfh.h    |  6 +++---
>  fs/nfsd/vfs.c      | 52 +++++++++++++++++++++++++++++++++++-----------------
>  fs/nfsd/xdr4.h     | 11 -----------
>  6 files changed, 97 insertions(+), 48 deletions(-)
> ---
> base-commit: c9194156c1039499533303fc63a66b0f1399896b
> change-id: 20230720-bz2223560-9c4690a8217b
> 
> Best regards,
> -- 
> Jeff Layton <jlayton@xxxxxxxxxx>
>